One of the most annoying issues with Linux’s graphical system (and any UN*X), is that if you have some keys setup for switching the keyboard layout – when using two or more keyboard layouts, such as for writing English and Hebrew – then that key combination cannot be used in any other keyboard shortcut.

Its most annoyingly present when setting the keyboard layout switching command to ALT+SHIFT (like in MS-Windows), then you can’t do any keyboard shortcut that has ALT+SHIFT in it – such as ALT+SHIFT+TAB to move to the previous window.